Transmission



Sept. 16, 1941. E. ORSHANSKY, JR 2,256324 TRANSMISSION Filed July 20,1939 11 Sheets-Sheet 2 v INVENTOR MY W ATTORNEYS Sept. 16, 1941. IoRsHANsKY; JR

TRANSMISSION 11 Sheets-Sheet 3 Filed July 20, 1959 all INVENTOR I Bfiwmwnfifz MKM M ATTORNEYS Sept. 16, 1941.

E. ORSHANSKY; JR TRANSMIISSION ll Sheets-Sheet 4 Filed July 20, 1939rNvr-iN roR v I $6 11512.2 mi}, M ATTORNEYS Egg W p 1941- I E.ORSHANSKY, JR- 2,256,324

TRANSMISSION 'Filed July 20, 1939 11 Sheets-Sheet 5 as ,my

108 101 103 lNVE NTOR 1511a: g rlamly, Jr

W km (W ATTORNEYS Sept. 16, 1941.

E. ORSHANSKY, JR

TRANSMISSION Filed July 20, 1959 11 Shegts-Sheet 's 10.9 J ans 9,

4 MW M ,ATTORNEY sg pt. 16, 1941. E. ORSHANSKY, JR

TRANSMISSION 11 Sheets-Sheet '7 Filed July 20, 1939 [lids 013141151ATTORNEYS P 1941- 2 E. oRsH NskY', JR 2,256,324

TRANSMiSSFlIQN Filed July 20, 1939 11 Sheets-Sheet 8 III/714 I/I/IIIII 7ATTORNEYS p I E. ORSHANSKY, JR 2,256,324

p 1941-. E. ORSHANSKY, J R 2,256,324

' TRANSMISSION Filed July 20, 1959 11 Sheets-Sheet 1o 1.31 INVENTORATTORNEYS Sept. 16, 1941. E. OR'SHANSKY; JR 2,256,324

TRANSMISSION Filed July 20, 1959 11 Sheets-Sheet 11 BB BB INVENTOR mu g/1 zzsly, I W

ATTORNEYS operated with variable torque.

Patented Sept. 16, 1941 UNITED STATES PATENT OFFICE 'rmmsrnssron EliasOrshansky, Jr., University Heights, Ohio, as-

signor to The'Acrotorque Company, Cleveland, Ohio, a corporation orConnecticut Application July 20, 1939, Serial No. 285,554 11 Claims.(01. Ii-189.5),

This invention relates to a structurally and functionally improvedtransmission and in'its more specific aspects aims to provide ahydromechanical transmission.

As such, it is an object of the invention to furnish an apparatus ofthis character which may be employed in connection with various types ofmechanisms such as motor and rail vevalve assembly by means of which theoperation or the transmission is governed;

hicles, power shovels, machine drives and in other installations whereit is desired to furnish driving and driven shafts or members and inwhich these elements may rotate through various speed ranges and inwhich the driven element will be A further object is that of providing aunit of this type and which will embody a mechanism I such that withinthe control of the operator, in-

finite variations in speed may be imparted to the driven element whilethe driving element or shaft has a substantially constant rotation.

A still further object is that of providing a hydro-mechanicaltransmission in which the aforementioned results may be achieved in anautomatic, or semi-automatic manner.

An additional object is that of constructing a unit of this type which,consistent with the achievement of the foregoing results, will cmbody arelatively simple and rugged construction,

such unit being capable of operating under high pressures withoutdanger-to the mechanism.

With these and other objects in mind reference is had to the attachedsheets of drawings illustrating practical embodiments of-the inventionand in which:

Fig. 1A is a sectional side view taken through the forward portion of atransmission;

Fig. 1B is a similar view taken through the rear portion of thetransmission;

Figs. 2, 3, and 4 are transverse sectional views taken to one side ofthe center line of the transmission and along the lines 2-2, 3-3, and4-4 respectively. and in the direction of the arrows as indicated inFigs. 1A and 1B;

Fig. 10 is a transverse sectional view taken along the lines Ill-i andin the direction of the arrows as indicated in Fig. 9;

Fig. 11 is a partly sectional plan view of the mechanism as shown inFigs. 9 and Fig. 12 is a sectional plan view of a further valveassembly, forming a part of the unit; Fig. 13 is a partly sectional sideelevation of the units as shown in Figs. 7 and 8 and in assembledcondition; Fig. 14 is a sectional plan view taken along the lines il-lland in the direction of the arrows as indicated in Figs. 1A and 13; Fig.15 is a sectional side view lines l5- l5 and in the direction of thearrows as indicated in Fig. 14;

Fig. 16 is a transverse sectional view taken along the lines iG-Hi andin the direction of tional views taken along the lines i1 and Iii-i8-respectively and in the direction of the arrows as indicated in Fig.1A;

- Fig. 19 is a somewhat diagrammatic representation of the fluid circuitand pipe embodied in the unit; and

Fig. 20 is a view similar to Fig. 10 but showing a modified form ofconstruction and also 7 illustrating somewhat diagrammatically the cir-Fig. 5 is a rear view of the transmission with certain of the partsbroken away to disclose underlying constructions;

Fig. 6 is a sectional plan view taken through the rear casing portion ofthe transmission and showing partly in section and partly in elevationthe mechanisms contained therein;

.Fig. 7 is a perspective view of the primary driven shaft of thetransmission;

Fig. 8 is a similar view of the control member I associated therewith;

i5 and is mounted upon anti-friction bearings cult and piping involvedin connection with such a structure as distinguished from the circuitillustrated in Fig. 19.v

Referring primarily to Figs. 1A and 13, it will be seen that the numeralI5 indicates a driving shaft which may. be. coupled in any desiredmanner to a prime mover (not shown)- This shaft has-aflixed to its innerend a gear it with which the teeth of a number of planet gears i1 mesh.Preferably six of the latter are employed and the teeth of theseelements in turn mesh with the teeth of ring gear i8 secured to a hubI9.

Each of the planet gears mayi be mounted by antifriction assemblies 20.A collar or tube 2i is concentrically disposed with respect to shaft 22.The inner end of this tube terminates in a flange 23 within whichassemblies 20 are fixed, so that as the latter have planetary movement,the tube or collar 2] is rotated. In addition to bearings 22 interposedbetween tube 2| andshaft l5, bearings 24 encircle the tube and serve tosupport the same with respect to the housing 25.

Fig. 9 is a face view of the control box or A radial series of cylinders26 is in turn supporttaken along the and 4|.

' by the latter.

ed by this housing and these cylinders as shown may be-seven in number.Within each of the same, a piston 21 is disposed for reciprocation andto each of these pistons a connecting rod 28 is pivotally secured andterminates in an arcuate contact portion 29. These portions engage andare actuated by an eccentric 30. They are maintained againstdisplacement with respect to the same, or each other, preferably bymeans of a pair of retaining bands 3| which encircle the contactportions 29 and ride within grooves formed in the outer faces of thesame.

Collar 2| is formed with cam portions 32 and 33 to one side of the planeof the cylinders 26. Also, extending from the cylinders 28 are pas-vsages 34 and at this time it will be noted that the presently describedcylinders as well as those hereinafter referred to, preferably havetheir outer ends closed by plugs or head caps 35. The passages 34 extendto chambers, the outer endsof which are closed by caps 38 and in turnextending from these chambers are passages or manifolds 31 and 38, theformer being a highpressure passage, while the latter is a low-pressurepassage, the relative disposition of these manifolds being especiallyillustrated in Figure 18.

of tube portions. The structure of these elements may be best understoodby referring to prior United States Patents 2,074,034, 2,098,115,2,116,749, owned by the Eaton Manufacturing Company of Cleveland, Ohio.These patents exemplify the structure which is preferably embodied atthis point.

With the foregoing in mind it will be understood that with shaft l5rotating, gear IE will be rotated to cause rotation of planets I'I.Ifhub l9 offers relatively little resistance to turning, then it will beapparent that planets I! will rotate and, therefore, shaft l5 will drivegear l6 and gears II to rotate gear I8 and consequently turn hub IS in adirection reverse from that in which shaft l5 turns. This will occur dueto the fact that tube or collar 2| will, of course, offer resistance torotation because it drives the pump ance to turning, then it is apparentthat as shaft To govern the flow of fluid through passages 34, 31,- and38, valve mechanisms are disposed within the chambers afore referred to,these units being particularly shown in Figures 1A or.17. Each of thesemechanisms'are preferably contained within a liner 39 formed with portsIt is to be understood that for each of the cylinders 26, a pair ofthese valve mechanisms are provided. One of these mechanisms will haveits port 4| aligned with passage 31 while the adjacent mechanism willhave its port aligned with passage 38. Each of the valve assemblieswill, of course, have its port 40 aligned with passages 34 of a givencylinder, and at this time it is to be appreciated that passages 31 and38 are, in effect, manifolds ,common to all of the cylinders instead ofbeing merely passages individual to the same.

Within each of liners 39 there is disposed a rod 42, themovements ofwhich may be guided by extending in slidable contact with the surfacesdefined by openings formed inouter and innerplates or disks 43 orthrough assemblies carried A valve body 44 encircles rod 42 andpreferably includes as shown an inner portion 45, an outwardly extendingcentral portion 48, and an inwardly extending upper portion 4'! uponwhich a clamping ring 48 is mounted.

Between ring 48 and the outwardly extending central portion, packing 49may be disposed in order to guard against the escape of fluid at thispoint. A spring 50 encircles rod 42 and bears against the reduced lowerend portion of the valve body so that such body is at all timesmaintained in contact with a collar or shoulder portion 5| associatedwith rod 42. Also, by mea s of this spring, the valve body tends to moveinto contact with its seat which is provided by en-' larging the lowerportion of the liner 39 and inwardly of port 4i so as to be contactiblewith the inner edge of the enlarged central portion 46 of the valvebody. It is, of course, to be understood that these adjacent surfacesare ground so as to assure a proper contact which will provide aneffective liquid seal even although high pressures are developed.

I5 rotates to turn gear l5, the gears I! will in addition to rotatinghave a planetary or orbital movement. In view of the fact that suchmovement will cause rotation of flange 23, tube 2| will be turned. Thisturning will result'in re.- ciprocation of the pistons 21 andsimultaneous actuation of the valves which are operated by cam tracks 32and 33. Alternate valves being connected to the high pressure and lowpressure passages or manifolds 31 and 38 respectively-and the partsbeing properly timed, it follows that as any individual piston movesthrough its suction stroke, itwill draw liquid through passage 34 frompassage or manifold 38 and will then exert pressure on this liquid toexpel the same through high pressure passage or manifold 31. Hub I9 iscoupled'to a driven member generally indi ted at 53, the detailedconstruction ofwhich i especially shown in Figures 7, 8, and 13, andwhich will be hereinafter described. This 'member is encircled by a cam54 in the form of aring, this cam being coupled to member 53 in a mannerhereinafter brought out. Encircling cam 54 are a series of radiallyextending cylinders 55 within which pistons 58 reciprocate, thesepistons actuating cam 54 and the assembly being generally similar tothat heretofore described in -connection with the structure identifiedby numerals 28 to 3| inclusive. At this time it will also be observedthat hub I9 is provided with cam portions 51 and 58 which actuate highand low pressure valves respectively for each of cylinders 55. Thesevalves preferably correspond in structure identically with the valvesheretofore described in association 'with the pump embracing thecylinders 28. For this reason the same refsure into manifold or passage31 and will be ad- Interposed between the inner ends of rods 42 andcams32 and 33 are elements 52 in the nature mitted by the valvesassociated with the motor to those cylinders of the latter within whichpistons are performing a working stroke. Thus, the motor will, throughcam 54 or any equivalent structure coupling the same to driven member53, serve to rotate the latter.

Consequently if the load on member 53 is slight, an operating conditionwill prevail which will substantially result in shaft I driving hub l9and member 53 through gears l6, I1, and 18 and in a direction reverse tothat in which shaft l5 rotates. If resistance to movement on the part ofmember 53 exceeds the force required to operate the pump, pistons 21will be reciprocated incident to the orbital movement of gears l1 andconsequent turning of tube 2|. Accordingly, fluid under pressure will bepumped to the motor and the latter will assist in rotating member 53. Ofcourse, as soon as this member begins to rotate, a certain amount ofdriving force will be transmitted through gears l6, l1, and I8 and,therefore, a mechanical drive will be established which will supplementthe efforts of the hydraulic drive.

- In fact, as the torque decreases, the mechanical drive willincreasingly supersede the hydraulic drive until finally a condition maybe approached such as has been 'afore outlined when it was assumed thatthe resistance to turning offered by member 53 was less than thatrequired to operate the pump.

A factor which contributes tothe greatest extent to the commercial andsuccessful operation of this unit is that the latter is in effectleakproof. In other words, cylinders 26 each have merely one-outlet, towit, the passage 34. Each of the valves associated with both the pump aswell as the motor are also in effect leak-proof pistons or against ahead of fluid under pressure, but may freely function as rods 42 aremoved against the relatively minor resistance offered by springs 50.

It is to be borne in mind that member 53 will be rotating in a directionopposite to the rotation of shaft l5, and while not essential, it isusually desirable that the ultimate driven. shaft or element 59 shallrotate in the same direction as that in which shaft 15 rotates. Withthis thought in mind, there is aflixed to the outer or rear end ofmember 53 a plate 60 which has coupled to it' a ring gear 5|. The teethof the latter mesh with planets 62 which in turn mesh lAand 1B, andassuming member 53 to be ro-' tating in a given direction, it will beunderstood that no drive will be imparted to the driven shaft 59 in thatring gear 6| will simple rotate to rotate the planets 62 which willmerely have orbital movement around sun gear 63. Thus, with theslightest resistance to movement on the part of shaft 59, no drive willoccur.

Asclutching element 68 is shifted to the left as viewed in FigureslB and6, the movement on the part of ring gear 6| will result in correspondingmovement on the part of. element 68; this movement will in turn resultin movement being implanet cage. .Thus, this cage will be caused torotate in synchronism with member, 53 and no movements willoccur betweenplanet 62 and-ring gear 6|. Consequently, there is in effect provided arigid coupling between member 53 and driven shaft 59 and the latter willrotate in the same direction as member 53. This would ordinarily bedesirable where a reverse drive is to be effected by the, transmission.

Where, however, a forward drive is to be achieved (i. e, one in whichshaft 59 is rotated in the same direction as shaft l5) the operator.

will simply engage element 68 with-brake teeth or portion 61. Underthese circumstances, the assembly is prevented from having orbitalmovement. It follows that as ring gear 6| rotates, the bodies of theplanets 52 will correspondingly rotate to turn in a-reverse directionthe sun gear 63 and the shaft 59 in order to achieve the resultsdesired.

As afore brought out, it is apparent that the fluid from the pump flowssubstantially without any obstruction or diminution in pressure or flowto the motor, and that both of these units are of the positivedisplacement type. In order that variable torque may be achieved, it isintended that the internal capacity of the motor may be capable of beingvaried in order that the latter may serve as a metering device for thepump. Now, in order to achieve this result, the cam ring 54 will,according to the present invention, be capable of being shifted so thatits degree of eccentricity with respect to the axis of member with a sungear 63. This sun gear is integral' with or coupled to the drivenelement or, shaft 59. Anti-friction bearings 64 may be provided atsuitable points so as to rotatably support the several elements and alsoas shown, an oil packing 65 may be interposed between the housing andthe shaft 59. I

Finally with respect to this portion of the structure, it is to beobserved that the rear edge of the ring gear 6| may be provided with aclutch portion 66 while a similar brake portion 61 may be aflixed to thehousing of the transmission. A clutching element 53 may be engageablewith either of these clutch or brake portions and be slidably mounted asat 59 upon a member 10. Selective coupling between the element 68 andclutch and brake portions 66 and 51 may conveniently be provided for bya shifting fork or member II, and at this time it is to be noted thatthe element 58 may in efiect form a continuation of the cage 12 whichsupports the planetS 62, c

With the parts in the position shown in Figures 53 may be varied. Thestructure by means of which this result may be achieved may be bestunderstood by referring to Figures 2, 7, and 13 taken in conjunctionwith the first figures- In Figure '7 it is primarily to be observed thatmember 53 may conveniently include endportions 13 to which hub l9 andplate 60 are respectively secured. Its central portion is generallyangular as indicated at 14 and has formed in it a pair of flattened andpreferably recessed surfaces 15 which are oppositely located, as well asa pair of grooves or track-ways l5. Mounted for sliding movement withinthe latter is a block 11 which is formed with a series of angularlyextending grooves I8 as well as xa series of tangentially extending andintersecting grooves 1.9 which may bedeeper than grooves 18.

Disposed to each side of the central body portion 14 are members whichhave their outer faces curved as is especially shown in Figure 2. Thesemembers are fixedly secured as, for example, by bolts 8| to the innerface of ring 54. The inner faces of these members 80 are provided withgrooves defining tangentially extending ribs 92 riding within grooves18; It is, of course, to be understood that blocks 11 are disposed onewithin each of the grooves I6. Consequently, the cam ring 54 members 80and 53 provide in coni. e., the latter will be concentrically and evenlyspaced from the axis of member 53, while the opposite extreme positionof the parts is shown in Figure 2. I

As heretofore described, it is obvious that member 53'will be incapableof longitudinal shifting within the unit. Likewise, ring 54 will beincapable of such shifting due to the manner in which it is mounted andforms a part of the fixed motor structure. Accordingly, if blocks 11are, for example, coupled by means of ribs 83 with an anti-frictionalbearing 84 and the latter is shifted longitudinally of member 53,members 88 will be projected and retracted as afore described. It isalso apparent that if the eccentricity of the motor operating ring orits equivalent is varied to a greater or lesser extent, the

' unit would become unbalanced.

Now with a view toavoiding any such result, it is preferred to employ acounter-balance of, for example, the type shown in Figures 13, 14, 15,and 16. In these views the numeral 85 indicates a disk or wheel whichmay have its periphery thickened and which is formed with a relativelylarge central opening 85. Both faces of this disk are grooved as shownat 81 and 88, the former groove preferably having its ends open. Bracketelements in the nature of angle irons 88 and 88 are-secured to member 53and are mounted in opposed pairs. within the recessed surfaces 15. Thedisk 85 is mounted for sliding movement between these pairs of bracketsand by introducing the outwardly extending arms of the same withingrooves 81 and 88 respectively. Afiixed to the disk 85 are a pair ofbracket elements 8| which have projecting portions 82 riding withingroove 18 of blocks 11.

Incident to the brackets 88 and 88, disk 85 may not shift longitudinallyof member 53. As a consequence if bearing 84 is shifted as aforedescribed to slide blocks 11 along member 53,-

which will serve to shift bearing 84 and blockmembers 11, it willbeobserved that as shown in Figure 6, it is preferred to employ a yoke85 which may extend above and below the bearing and to each side of thesame. By means of pin 81 this yoke is rockingly coupled to the bearingand each end of the yoke is coupled to a piston rod 88 in the form of asleeve encircling a guide 1 rod 88. Only one of the latter assemblieshas been illustrated in that the second of the same involves a mereduplication, and as will be seen, still'referring to Figure 6, a pistonI88 provided with suitable packing IN, is slidably enclosed within aliner I82, in turn enclosed by a cylinder structure I83. The oppositeends of rods 88 may be supported respectively in a bracket I84 and thehead I85 of the cylinder. The outer faces of the liner may be grooved toprovide passages. I88 and I88 having openings II8 communicatingwith theinterior of the liner and within which the piston reciprocates. Portionsof the casin may be formed withpassages I85 terminating in outlets I81registering with the passages I88 and the movement of one of the pistonslags behind the movement of the other of the same, no binding of theparts will occur because the yoke will equalize this .action.

Now to control the flow of fluid through passages I85, avalve structureis employed and bracket portions 8| will cause the eccentricity ofmember 85, with respect to the center of member 53, to be varied. Withthe parts mounted as shown, the eccentricity of the disk will beincreased as the eccentricity of ring 54 is increased, it being ofcourse understood that the outermost surfaces of these elements will bespaced one hundred and eighty degrees. As the blocks are shifted in anopposite direction, the eccentricity of the disk 85 will be decreasedsimultaneously with the decrease in eccentricity of ring 54. Thus, acounter-balance is provided and the action of which is increased ordiminished in proportion to the diminution or increase in eccentricityof the -motor operating element and both of these parts which isenclosed within a casing III applied to.

the main casing as best shown in Figure 19. The interior of this valveis best illustrated in Figures 9, 10 and 11. As shown, a recess IIZ maybe provided within the body III and extending vertically of this recessa shaft II3 may be mounted. The latter is encircled by' a sleeve I I4provided with three pairs of arms II5. In line with the arm of one ofthese pairs is a piston H8 and -in line with the second arm of this pairis a spring I", the compression of which may be adjusted in any desiredmanner (not which may mount adjustable head portions H8. Adjacent theinner ends of these rods are ball valves I28, spring pressed as atI2I,and cooperable with seats I22. The latter defines the entrance to abranch passage I23 coupled-to one of the pairs of passages I85. So thatno misunderstanding may occur, it is at this time to be emphasized thatas shown in Figure 10, one of the passage portions I communicates, forexample,with the forward end of one cylinder liner I82, while the otherof the same communicates with the corresponding end of the secondcylinder liner.

As illustrated in Figure 9, each one of the secondpair of arms contactsone of a pair of rods shown); In line with the next pair of arms are rodH8 I I8, while the arms of the third pair are adjustably coupled tospring pressed valve elements I24 which guard against the flow ofliquid-from branch passage I25 to branch passage I26.

Consequently, with sleeve I I4 rocked in one direction, rod II8 may bemoved to unseat valve I20, but due to the forked connection I21 existingbetween the third arm and valve I24, the latter will not be unseated.However, thecomplementary rod portion H8 and valve I24 cooperative withthe opposite arms of the second serve to control the flow throughpassages precisely as may'occur in the structure in Figure 10, exceptingthat these passages I06 are coupled, for example, to the rear or outerends of the cylinder liners.

Now referring back to Figure 1A in conjunction with Figure 19, it willbe observed. that while not essential it is preferred to employ whatmight be termed an auxiliary pump I which may be driven by a gear I29affixed to shaft I5. This pump is a relatively low pressure unit and isprovided with an,outlet I30 from which a branch I3I extends to recessesI32 forming'a part of the main casing enclosing. elements to supplylubricant to the same. Outlet I is continued as in Figure 19 and extendsto a pressure tank I33 which may be located above the plane of thetransmission. Outlet conduit I30-may also be furnished with a branch I34connected one to each of the fittings I35 (one of which is shown inFigure 10) a Moreover, as shown in Figure 1A, I

tubes I36 and I37 are connected respectively to the high pressure andlow pressure manifolds. The former tube continues as shown in Figure 19and is coupled with the inner end of cylinder I3'I within whichpiston H6is movable.

Consequently it follows that if very little pressure exists within thehigh pressure manifold and as would be the condition if the unit weresub jected to relatively little torque, the pressure would remainseated, while valve I24 would be unseated. Thus, fluid would be ventedfrom one i of the ends of cylinders I02-I03 through a pair of thepassages I06, the branch passage I23, past the valve I24, and bedischarged through branch passage I26. However, fluid under pressurewould be introduced into the opposite ends of the cylinders incident tothe unseating of valve I20 which would permit liquid under pressure toflow through fitting I35, branch passage I23, and passages I06. Thiswould have the result of causing both pistons I00 to be shifted to theirextreme positions and to correspondingly move yoke member 96 and blocksTI to cause a minimum condition ofeccentricity of the pump, rotor, andcounter-balance.

If, however, the parts have been operating under substantially theseconditions and, for example, the torque on the unit increases (as wouldbe the case if the loadon the driven shaft were increased for somereason) it is obvious that the Urider these cirpressure within the highpressure manifold would 75 one side of the pistons increase.Accordingly, liquid under pressure would be forced through tube I36.This pressure will result in the piston II6 being projected to compressspring III. of course, it will be appreciated that the compression ofthis spring will be most carefully adjusted for each given installationand so that the controls act autothe entire transmission to the torqueload. Thus,

with spring II 'I compressed, the arms II5 are' rocked in a manneropposite from that just described. Under these circumstances, the valveI20 which has just been considered, remains closed and valve I24 whichhas just been considered, is open. Conversely, the complementary valvesI20 and I24 coupled to the opposite arms of the last two pairs, arerespectively opened and maintained in closed positions. This will havethe obvious result of allowing liquid which has heretofore been forcedunder pressure and to I00 to be discharged through the passages I06,past valve I24, and through passage I26. At the same time, fluid underpressure will be introduced to the opposite sides of the cylinders byflowing past valve 1 20 which has been unseated. Consequently, yoke 96will now be shifted to correspondingly move blocks 11. This will causean increase in the cocentricity of ring 54 with respect to member 53, orin other words, thestrokes of the motor pistons will be increased inrange. As a consequence of this increase of internal capacity on thepart of the motor, the torque developed by the unit will be increasedand when a pressure condition within the high pressure manifold isestablished such that spring I" maintains the piston H6 in normalposition, no further variation in eccentricity will occur. Also asheretofore traversed, as soon as the load on the unit decreases to'asuflicient extent, spring I I1 will cause a retraction of piston II6 sothat the internal capacity of the motor will again be adjusted resultingin a maximum speed of rotation on the part of the driven shaft. Witheach such adjustment, it will of course be understood that acorresponding adjustment of the counter-balance occurs so that asubstantial condition of static and dynamic balance is maintained.

By the provision of pump I28 the sump level is maintained and all partsof the apparatus are adequately lubricated. Moreover, with the provisionof this pump, a priming function is achieved. This is-quite aside fromthe fact that the pump in the embodiment under consideration serves asheretofore described to operate the controls. The tank I33 may be, forexample, under a pressure of twenty pounds to the inch 7 and with a viewto distributing any surplus liquid, a pipe I3'I may extend from the tankto the manifolds. .This pipe may have interposed casing I39 may befurnished from whichacontrol rod I 40 extends. This rod may-be coupledto a lever'or pedal that it may be conveniently projected by theoperator. As will be observed, the feed line I36 extending from the highpressure manifold may conveniently be provided with .a branch I4Icoupled to casing I39 and lead I31 is also coupled to this casing. Atthis time it is also to be noted that a return line I42 is coupled topump I28 and connects to the sump within the main casing of theapparatus.

Attention is next directed to Figure 12 in which it will be noted thatthe interior of casin I38 has been shown. As illustrated a/passage I43connects with high pressure line I36 while a passage I44 communicateswith line I31. A passage. including a valve seat I45 affordscommunication between passage I43 and I44 and further passages I46 andI41 arealso furnished to extend between the first named passages. Avalve I48 having a line-seal contact cooperates with seat I45-and aspring I48 normally maintains this valve on its seat. A guiding pistonor plunger I50 forms apart of valve I48 and extends into a bore in linewith the axis of the valve seat I45.

It follows that with passages I46 and I41 sealed, an operator by simplyraising the rod or actuating member I40 against the action of springI40, will permit fluid to flow from pipe I36 through pipe I31.Consequently the pressures in the high and low pressure manifolds willbe equalized and no power will be transmitted by the pump to themotor.Under these circumstances no drive will be transmitted from shaft I5 todriven member 58. When it is desired to again rotate the driven memberthis may be accomplished by simply releasing the rod I40 or itsequivalent. Such release will allow valve I48 to move onto seat Il45,thus again iso- 1 within the unit and if not counteracted would resultin a series of impulses being transmitted to the driven member. Thisobviouslyv would be objectionable. The plungers I5I and I52 will serveto counteract this in that any sudden in crease of pressure withinpassages I43 and I44 would result in a certain amount of liquid actingagainst the ends of these plungers,- and this action would open passageI46 or I41 to a greater or lesser extent to by-pass what might be termedthe peaks of the pressure surges and thus cushion and smooth out theoperation of the unit. The reason for providing plungers in associationwith both the high as well as the low pressure manifolds is becauseunder certain circumstances the apparatus to which the driven end of thetransmission is coupled may in effect be driving back through thetransmission towards the prime mover. Under these circumstances it ispossible that high pressures would'be developed in what is normally thelow pressure manifolds so that in eflect the motor would be operatingthe pump. It is under such circumstances that plunger I52 functions.

While under most conditions it is preferred to employ a supplementary orauxiliary pumping .to passage I64 and so into passages I06.

. I51 is mounted, such valve being normally spring pressed as at I58into contact with the seat I59 in conjunction withwhich it forms a lineseal.

A stem I60 projects beyond the valve body I51 and is engageable with arod or tappet I6I corresponding in function to rod II8 described inconnection with Figure 10. Also similar to the structure employed inthat view, a pair of valves I62 are employed which are spring pressedand correspond to valves I24. These valves control the flow of liquidthrough a passage I 63 and a branch to a passage I65 which is coupled tothe return line I31.

Thus, it is obvious that according tothe movement-of piston .II6, thepairs of arms will be rocked. Movement of the center pair of arms willresult in an unseating of oneof .the valves I51, allowing a flow ofliquid from branch I 54 Simultaneously the opposite valve I62 controlledby the third pair of arms will be withdrawn from its seat and will allowa flow of liquid from the cylinders through passage I06 and passage I64to passage I65 and thence through line I37".

unit I28, this unit may be dispensed with and ing the tappets orelements 52'and priming the apparatus without being utilized for controlpur poses. Such a constructionhas been shown in This will vent that endof the cylinders which is connected to the latter pair of passages I06.

It is believed that as a result of the foregoing review it would bemerely repetitious to traverse again the several phases of operation ofthe unit as included in the transmission. Suffice it to say that thereis herein provided a hydro-mechanical transmission embodying functionaland structural improvements and which may be empldyed to drive a shaftor other member in a forward or reverse direction and under varyingconditions of torque while for example-although not necessarilythedriving shaft or prime mover maintains a substantially constant R. P. M.and develops a predetermined amount of driving force. Proportional tothe load placed upon the transmission, the latter'will automaticallyvary the internal capacity of and driving force exerted by the motor.Consequently, the oper-. ator will not have to concern himself with.constantly and accurately adjusting themotor to serve as a meteringdevice ,for the pump. However, the operator may bring the driven shaftto a complete standstill by simply actuating theimum capacity, or inother words, its eccentric will present a maximum throw, arotation ofthe motor will occur. This in turnwill result in a rotation of thedriven shaft. 'Due to the manner in which the valves are timed, suchrotationas shown in the drawingswill be in a counter clock-wisedirection. Similar rotation will be imparted to the orbit gear. 7 in thegear unit,

I clock-wise rotation of the sun gear and counter clock-wise rotation ofthe orbit gear will cause the carrier member to approach and finallyreach zero rotation. This, of course, will only occur as the loaddiminishes due to the increase of momentum of the vehicle and especiallyin the 'case of light load being involved. Of course, if

-centric with respect to the shaft at which point the motor will notfunction.

Viewing the sequential functioning of the parts, it is obvious that asthe eccentricity of the motor crank diminishes, the capacity of themotor decreases and it is incapable of receiving as much fluid from thepump as theretofore. Consequently, a gradual slowing up of the planetarycarrierwhich drives the pumpis permissible because the pump output isbeing reduced. When the motor capacity reaches zero-incident to theadjustment of the eccentricthe pump (which has been gradually slowingdown) comes to a complete stand-still because the motor acts, in

effect, as a valve which shuts off the flow of oil from the pump. Underthese circumstances, shaft I5 will be turning clockwise. The plane-'tary carrier will be standing still and the orbit gear mounted oncarrier l9 will be rotated in a counter-clockwise direction.

Thus, it is apparent that th capacityof the motor is correlated by theeccentrics to the ca-.

pacity of the pump. When the pump reaches zero'speed, the motor has zerocapacity and the transmission is in what might be termed a directmechanical drive." Were it not for this variable feature, the unit wouldbe inoperative except at one pre-determined speed.

The adjustments make for the variation of speedof the driven shaft 53and under constant speedconditions of the shaft I 5, i. e., if the speedof the pump driving member 2| diminishes, morepower will be transmittedby the mechanical couplingof the transmission and less will betransmitted by the hydraulic coupling.

v Accordingly, the speed of shaft 53 will increase until it reaches themaximum determined by the proportions of the gears. At this point, allof the power is transmitted by the mechanical cou-v pling or side of thetransmission and 'zero power is transmitted by the hydraulic coupling orside of such transmission. v The control means areautomaticallyresponsive to the oil pressure within the unit and thus area measure of engine torque. Furthermore, when the torque increases'beyond a pre-determined amount, the resultant pressures will cause ashifting of the eccentric in the direction of greater eccentricity. Whenthe oil pressure (engine torque) decreases below a'certain amount, thecontrol will shift the eccentric in the direction of lessereccentricity. Otherwise stated, the eccentric will always be in such aposition'that if it shifts in the direction of greater eccentricity,

the oil pressure will diminish, whereas, if it shifts in the directionof lesser eccentricity, the

oil pressure will tend'to rise. The positionof the eccentric will bedetermined by the fact that the engine is driving the load. If the loadtends to increase in a direction approaching th capacity of the engine,the oil pressure will increase and will cause a shifting of theeccentric to increase the capacity of the motor and this will relievethe load on the engine by introducing a a reduction range. This in turnwill cause a diminution in the fluid pressure and th engme or j primemover will now tend to speed up.

It will be understood that as the eccentric shifts to vary the internalcapacity of the motor, the counterbalance will shift in adiametricallyopposite direction, so that the parts will be insubstantial balance. Moreover, it will be understood that slippage ofthe parts, with respect to each other, will b substantially absent,irrespective of the viscosity, pressure, and temperature of the oil.This is due to the fact of the line-seal type of valve constructionwhich em braces relatively large and relatively small surfaces.Accordingly, viewed from one aspect, we have, in the present disclosure,what in effect amounts to a substantial knife edge portion, and

which will cooperate with an adjacent sealing surface so as tosubstantially interrupt the oil or fluid films between those surfaces.

minute'as to be of no consequence, or else such flow will benon-existent, irrespective of the pressures which occur. It will alsobe-appreciated, with respect to the valve assemblies, that they are insubstantially balanced condition. In other words, only relatively smallforces will be required to seat or unseat the same, and in theiroperation, no pumping of fluid will occur.

Thus it is obvious that among others the several objects of theinvention as specifically afore noted are achieved. Numerous changes inconstruction and re-arrangement of the parts might be resorted towithout departing from the spirit. of the invention as defined by theclaims.

I claim:

1. A transmission capable of delivering on the part of the output shaftdriving torque in excess a gearing assembly comprising threeintermeshing gears, two of the gears of, said assembly being coupled tomove with said driving and driven shafts, the third gear moving inresponse to relative movements of said .first named gearsand providing areaction point for-the same such that power is transmitted from saiddriving shaft to said driven shaft, a pump unit connected to said thirdgear to be driven thereby; a motor unit connectedto'said driven shaft,means providing an unobstructed passage'from said pump to said'motorwhereby fluid will flow without reduction of pressure or volume fromsaid pump to: said motor, a variable eccentric forming a partof saidmotor and whereby the internal capacity of said motor .unit may becorrespondingly varied so that said motor unit will function asa-me'tering device to control the volume of fluid delivered by said pumpand a counterbalance associatedwith said motor unit ,to'sub-,stantiallycounteract any condition of unbalance, v

as developedbysaid eccentric. g

2. A transmission capable of delivering on the part of the'output shaftdriving torque in excess Conse- 'quently, any flow which will occur willbe so a gearing assembly comprising three intermeshis ing gears, two ofthe gears of said assembly being coupled to move with said driving anddriven shafts, the third gear moving in response to relativemovements ofsaid first n amed gears and providing a reaction point for the same suchthat power is transmitted from said driving shaft to said driven shaft,a pump unit connected to said third gear to be driven thereby, a'motorunit connected to said driven shaft, meansproviding an unobstructedpassage from said pump to said motor whereby fluid will flow withoutreduction of pressure or volume from saidpump to said motor, a variableeccentric forming a part of said motor and whereby the internal capacityof said motor unit may be correspondingly varied so that said motor unitwill function as a metering device to control the volume of fluiddelivered by said pump, a counterbalance associated with said motor unitto substantially counteract any condition of unbalance as developed bysaid'eccentric and means operable in response to the pressures developedby said pump unit for automatically shifting said eccentric andcounterbalance. v

3. A transmission capable of deiiverin 'on the part of the output shaftdriving torque in excess of that imparted to its'input shaft, saidtransmission including a driving shaft, a driven shaft, agearingassembly comprising three intermeshing gears, two of the gears ofsaid assembly being coupled to move with said driving and driven shafts,the third gear moving in response to relative movements of said firstnamed gears and providing a reaction point for the same such that poweris transmitted fromsaid driving shaft to said driven shaft, a pump unitconnected to said third gear to be driven thereby, a motor unitconnected to said driven shaft, means providing an unobstructed passagefrom said pump to said -motor whereby fluid will flow without reductionof pressure or volume from said pump to said motor, a variable eccentricforming a part of said motor and whereby the internal capacity of saidmotor unit may be correspondingly varied so that said motor unit willfunction as a metering device to control the volume of fluid deliveredby said pump, a counterbalance associated with said motor unit tosubstantially counteract any condition of unbalance, as developed bysaid eccentric, pressure responsive means connected to the transmittingfluid in such transmission.

pump unit and to both said eccentric and councentricity of the crankportion of said motor, a counterbalance for said crank portion and meansconnected to both said counterbalance and motor crank portion forsimultaneously shifting the same, whereby the capacity of said motorunit may be varied and the forces set up by said crank portion maybecounteracted, pairs of valves corresponding in number to and disposedadjacent each cylinder of the pump and motor, one valve.

of said pair controlling the flow of fluid between the cylinder withwhich it is associated and the between such surfaces whereby leakage andslippage is substantially prevented irrespective of the viscosity,temperature and pressure of the power 5. A variable speed transmissioncomprising in combination a driving shaft, a driven shaft, meanscoupling said shafts, and including a torque applying driving connectioncomprising a pump unit operatively connected to said driving shaft, amotor unit operatively connected to said driven shaft, means providinghigh pressure passages for the flow of fluid from said pump to saidmotor, means providing low pressure passages for the flow of fluid fromsaid motor to said pump, at-

least said high pressure passages being free from valvular,pressure-aftectirig constrictions, said pump and motor each includingaplurality of centricity of the crank portion of said motor, a-

counterbalance for said crank portion and means connected to both saidcounterbalance and motor crank portion for simultaneously shifting thesame, whereby the capacity of said motor unit may be varied and theforces set up by said crank portion may be counteracted, pressureresponsive means connected to said high pressure passages and to saidshifting means for automatically operating the latter in response toincreasing and decreasing fluid pressures as developed by said 4. Avariable speed transmission comprising in combination a driving shaft, adriven shaft, means coupling said shafts, and including a torqueapplying driving connection comprising a pump unit operatively connectedto said driving shaft, a motor unit operatively connected to said drivenshaft, means providing high pressure passages for the flow of fluid fromsaid pump to said motor, means providing low pressure passages for theflowof fluid from said motor to said pump, at least said high pressurepassages being free from valvular, pressure-affecting constrictions,said pump and motor each including a plurality of cylinders, a shaft, acrank portion connected to said shaft, and pistons reciprocable withinsaid cylinders whereby the reaction of the pistons of the pump and motorunits upon the cylinders pump unit, pairs of valves corresponding innumber to and disposed adjacent each cylinder of the pump and motor, onevalve of said pair controlling the flow of fluid between the cylinderwith which it is associated and the high pressure passage, the othervalve of such pair controlling fluid flow between such cylinder and thelow pressurev passage, means causing timed movements of the valves ofeach cylinder with respect to the movements of the piston within suchcylinder, each of said valves including a seat element and a body,element, each of saidelements presenting surfaces cooperable with thesurface of-the adjacent element and means assuring a movement of suchsurfaces towards each other to interrupt the flow of fluid between suchsurfaces wherebyleakage" and slippageis substantially preventedirrespective of. the viscosity, temperature and pressure of the powertransmitting fluid in such transmission.

6. A variable speed transmission comprising in combination a drivingshaft, a driven shaft, a mechanical drive for said shafts and comprisinga differential mechanism forming a torque applying driving connectionincluding three in terconnected elements, two of said elements beingcoupled respectively to said shafts, and the third element beingdisplaceable relative to said two elements, a hydraulic drive forming apart of such transmission and including a system in which slippage issubstantially absent irrespective of the viscosity, temperature, andpressure of the power-transmitting fluid in such system, said drivecomprising a pump unit operatively connected to the third element ofsaid differential mechanism, a motor unit operatively connected to saiddriven shaft, means whereby at least one of said units may have itscapacity varied, means providing a high pressure passage for the flow offluid from said pump to said motor, means providing a low pressurepassage extending from said motor to said pump, at least said highpressure passage being free from valvular, pressure-affectingconstrictions, said pump and motor each including a plurality ofcylinders and pistons reciprocable within said cylinders whereby thereaction of the pistons upon said cylinders enable said motor to applydriving torque to said driven shaft, and in addition said high pressurepassages being free from valvular, pressure-affecting constrictions,said pump and motor each including a plurality of cylinders and pistonsreciprocable within said cylinders whereby the reaction of the pistonsupon said cylinders enable said motor to apply driving torque to saiddriven shaft, and in addition to the driving torque applied to saidshaft through the mechanical drive provided by said differentialmechanism, pairs of valves corresponding in number to and disposedadjacent each'cylinder of the pump and motor, one of th valves of eachpair controlling the flow of fluid between the cylinder with which'it isassociated and the high pressure passage, the other valve of such paircontrolling fluid flow between such cylinder and the low pressurepassage, means causing timed movements of the valves of each cylinderwith respect to the movements to the driving torque applied to saidshaft through the mechanical drive provided by said differentialmechanism, pairs of valves corresponding in number to and disposedadjacent each cylinder of the pump and motor, one of the valves of eachpair controlling the flow of fluid between the cylinder with which it isassociated and the high pressure passage, the other valve of such paircontrolling fluid flow between such cylinder and the low pressurepassage, means causing timed movements of the valves of each cylinderwith respect to the movements of the piston within such cylinder, eachof said valves including a relatively movable seat element and bodyelement, each such element presenting surfaces engageable with thesurface of the adjacent element, one of such surfaces being ofsubstantially reduced area in comparison with the surface with which itcooperates, and means assuring an engagement between such surfaces, suchthat the fluid film between the same is substantially ruptured.

'7. A 'variable speed transmission comprising in combination a drivingshaft, a driven shaft, a mechanical drive for said shafts and comprisinga differential mechanism forming a torque applyingdriving connectionincluding three interconnected elements, two of said elements beingcoupled respectively to said shafts, and the third element beingdisplaceable relative to said two elements, a hydraulic drive forming apart of such transmission and including a system in which slippage issubstantially absent irrespective of the viscosity, temperature andpressure of the power-transmitting fluid in such system, said 'drivecomprising a pump unit operatively connected to the third element ofsaid'difl'erential mechanism, a motor unit operatively connected to saiddriven shaft, means whereby at least one of said units may have itscapacity varied, means providing a high pressure passage for the flowof-Vfluid from said pump to said motor, means providing a low pressurepassage of the piston within such cylinder, each of said valvesincluding a relatively movable seat element and body element, each suchelement pre-' senting surfaces engageable with the surface of theadjacent element, one of such surfaces being of substantially reducedarea in comparison with the surface with which it cooperates, meansassuring an engagement between such surfaces, such that the fluid fllmbetween the same is substantially ruptured, means providing 4 recessesfor the guidance and housing of each of said valve bodies, said recessesand bodies each presenting wall portions, and a packing associated withone of said wall portions and slidably engageable with the second of thesame to provide a seal guarding against fluid leakage between said wallportions.

8. A variable speed transmission comprising in combination a drivingshaft, a driven shaft, means coupling said shafts, and including atorque applying driving connection comprising a pump unit operativelyconnected to said driving shaft, a motor unit operatively connected tosaid driven shaft, means whereby at least one of said units may have itscapacity varied, means providing high pressure passages for the flow offluid from said pump to said motor, means providing low pressurepassages for the flow of fluid from said motor to said pump, at leastsaid high pressure passages being free from valvular, pressure-aifectingconstrictions, said pump and motor each including a plurality ofcylinders and pistons reciprocable within said cylinders whereby thereaction of the pistons of the pump and motor units upon the cylindersthereof enable said motor to apply driving torque to said driven shaft,pairs of valves corresponding in number to and disposed adjacent'eachcylinder of the pump and motor, one valve of said pair controlling theflow of fluid between the-cylinder with which it is associated and thehigh pressure passage, the other valve of such pair controlling, fluidflow between such cylinder and the low pressure passage, means causingtimed movements of the valves of each'cylinder with respect to themovements of the piston within such cylinder, each of said valvesincluding a seat element and afbody eleme'nt, each of said elementspresenting surfaces ,engageable with the surface of the adjacentelement, the

area of one of such surfaces being materially I reduced in comparisonwith the area of the adextending from said motor to said pump, at least

